1. Field of the Invention
The present invention relates to a treatment apparatus, a treatment method, and a storage medium, which are provided to perform heat treatments such as a film formation treatment for depositing a thin film on the surface of an object (such as a semiconductor wafer) to be treated.
2. Description of the Related Art
It is general that heat treatments such as a film formation treatment, etching treatment, oxidation treatment, diffusion treatment and reforming treatment are performed on a semiconductor wafer including a silicon substrate in order to manufacture a semiconductor integrated circuit. The film formation treatment is performed in a batch type film formation apparatus, for example. Such batch type film formation apparatuses are disclosed in JP-A-8-44286, JP-A-9-246257, JP-A-2002-9009, JP-A-2006-54432, JP-A-2006-287194 and the like.
As shown in FIG. 10, semiconductor wafers W, which are objects to be treated, are held by a wafer boat 4 at multiple stages and accommodated in a vertical treatment chamber 2 made of quartz. A cylindrical heater 6 surrounds the treatment chamber 2 and heats the wafers W to a temperature approximately ranging from 600° C. to 700° C.
A gas supply unit 8 supplies a gas required for treatments to a lower portion of the treatment chamber 2. For example, a gas for film formation is supplied to the treatment chamber 2 for a film formation treatment. Simultaneously, the treatment chamber 2 is evacuated by a vacuum exhaust system 12 through an exhaust port 10 provided at a ceiling portion of the treatment chamber 2 to ensure that pressure of an atmosphere within the treatment chamber 2 is maintained to a predetermined level. Then, heat treatments such as the film formation treatment are performed.